package main

import "fmt"

func main() {
	var s, t string
	fmt.Scan(&s)
	for i, c := range s {
		az := (int('Z') - int('A') + 1)
		u := int(c) - i%az - 1
		if u < int('A') {
			u += az
		}
		t += string(u)
	}
	fmt.Println(t)
}